The one IPCC climate-tech chart you need to know

The Intergovernmental Panel on Climate Change (IPCC) released its latest report on Monday, outlining what needs to be done during this rapidly closing window of opportunity to mitigate global warming.

The nearly 3,000-page document, which is part of the IPCC’s sixth assessment of climate-change scenarios, points out that while the world has made some progress in slowing emissions growth, there is an urgent need to accelerate the reduction of greenhouse-gas emissions over the next few years.

“The report puts it pretty starkly that if we don’t enhance our ambitions in the next decade, if countries just sort of keep their current Paris Agreement pledges through 2030, it’s going to firmly put limiting warming to 1.5 degrees [Celsius] out of reach, and make it much harder to keep warming to two degrees,” Zeke Hausfather, climate research lead at Stripe and a member of the working group for the IPCC report that was released over the summer, told Emerging Tech Brew.

While the assessment called unproven tech like carbon removal essential to achieving net zero, it also showed that many of the tools needed to shift away from fossil fuels and make significant progress are already available. Namely, affordable renewable-energy sources and low-cost tech to improve energy efficiency.

Zoom in: One graphic from the report stood out as most important to Hausfather when it comes to thinking about the technologies needed to combat climate change. Here's the chart—keep reading for his take on why it's so important, and what it tells us:

The figure shows mitigation options grouped by sector. The length of the bars illustrate each solution’s potential to reduce emissions by 2030, measured in gigatonnes of CO2, and the colors reflect the current cost of each solution, measured in the price per tonne of CO2 in US dollars.

“This is highlighting the things that we need to do now, and in the next decade, to reduce emissions,” Hausfauther said. “This is the low-hanging fruit diagram.”

The graphic only assesses the promise of these technologies through 2030. While this means some solutions, such as carbon removal, which are expected to begin to scale later in the decade, aren’t accounted for, it emphasizes what can be done immediately to address climate change with the urgency the IPCC report conveys.

“The cheapest form of carbon removal is mitigation today. It’s always going to be cheaper to cut the tonne of carbon today—that we can—than it will be to suck that carbon out of the atmosphere later in the century,” Hausfather said.

As the figure shows, several existing solutions—like wind and solar, energy efficiency and demand management tools, and lower-emissions transit options, such as public transportation, bikes and e-bikes, and more fuel-efficient cars, trucks, ships, and planes—already have the potential to provide cost savings while reducing emissions.

And other technologies, such as electric vehicles, are expected to reach this kind of affordability within the decade.

EVs remain more expensive than their gas-powered counterparts, but there are cost savings over the lifetime of EVs in fleets, for example. Hausfather pointed out that the emissions-reduction potential of EVs in this chart is smaller than people might expect.

“The main reason is, this only goes through 2030. Electric vehicles, like buildings, are a stock problem,” he said. “It takes a long time to replace all the old gas vehicles. Which really means for those sorts of things, we need to start sooner rather than later, because there’s this big lag in the system in terms of the turnover of technologies that are in use.”

Driving down costs

There are still plenty of red and orange bars in the graphic, marking technologies that currently cost as much as $200 per tonne of CO2. While these mitigation strategies may not be cost-effective today, some may be crucial to meeting climate goals in the future, Hausfather said.

"We need to be investing in the technologies we’ll need to deal with the harder parts of the economy to decarbonize in the 2040s and 2050s,” he said. “We can do both. We can invest in maturing and driving down the cost of technologies we need in the future, while we deploy the heck out of technologies that we can today and that are mature today.”

This means deploying capital to commercialize tech like geothermal, advanced nuclear, and carbon-dioxide removal in particular, which are expensive today, but will be needed at a large scale later in the decade, he said.

“A lot of the time we talk about climate change like there’s a silver bullet,” Hausfather said. “This diagram really illustrates that it’s not a silver bullet. It’s a silver buckshot. There’s no single solution that’s even one-tenth of the entire thing. It’s really a huge variety of technological—and behavioral—changes across a variety of different sectors that's needed to put us on the path toward net-zero emissions.”